when you say "save it to reuse later", do you mean re-use in other tables/bases?

Each data view can have its own filter conditions, so you can create multiple views, each with its own conditions / condition groups. Use the view that has the conditions you want at the time.

You can also copy the filter conditions from one view to another. Note that this will copy all of the filter settings, not just one condition group.

Another option is to put the complex logic of your condition group into a formula field. Then filter on the formula field.

Not necessarily. Just in the same base. I created a condition group that had about 15 conditions in it. Then I needed it again; my only option was to do it all over adding each of the 15 conditions one by one. It would have been nice to just save that condition group with a name to reuse later.

Oh nice! In that case, kuovonne's answer seems like the way to go! You can just the filters from another configuration with those steps.